Method of receiving telegraphic signals.



:Eo. 81.2;557. PATENTED FEB. 1S, 1906L s. D. FIELD. METHUD OF REGBWIMG TELEGRAPHIO mew ALS APPLICATION FILED JUNE 10, 1905.

- riodic I nnirnn srrrrrs li fii. El lhil METHOD if)? REOElVlNGi 'i'ELEGlRAPHlC @llLlhiAL3.

Application filed June 10,

Specification of Letters Patent,

Patented Feb. 13, 1906 1905. Serial No. 264.676.

To add whom Wm concern.-

Be? it known that l, STEPHEN DUDLEY Fin/Ln, a citizen of the Uuitoijl fftatcs, residing; at Stoclrhridgc, in the county oi Berkshire and. State of Massachusctts, have invented certain now and useful improvements in ll'iethods of Receiving ".ielcgraphic Signals, of Which the following is a full, ch .ii', and cxa description.

My invention. relates to .rccciving apparatus for clectric'signaling systems.

in transmitting electric signals, and pan ti cularly in conncction with Wirelcis tclegris phy, an apparatus is often employed in which impulscs arc sent out of certain PI'GdBhGfiF mincd frequency or periodicity, and in order to properly receive these signals the receiving apparatus must he attuned or synchronized to correspond With the periodicity of thc i111- pulscs transmitted.

The object of transmitting and rcceiving the signals in periodic impulses is twofold. In the first place on account or" the strengtheningefiect of resonance, the receiving apparatus can he inadc torespond to much l echler impulses than would otherwise be possible, and secondly by the use of apparatus of dif ferent periodicity in the dillcrcnt stations, the receivers can be selective and respond to only particular messages.

The object of my present invention is to provide a'methorl for receiving signals cl any sort, having a periodic character, and to fun thcr provide a method. by which the periodicity can be varied, sothat any receiver can be rcadil y attuned to any kind of messages transmitted. In this way communication may he had With any one 01" a plurality of transniittin stations, sending messages simultaneous y, by merely attuning the rcccivto respond to similar impulses of any particular transmittlug-station.

A further object of my invention is to provide a method by which the periodicity oi the .rcceWing-station is made continuously vary ing; in its normal receptive condition so that ii is in condition to receive a. signal of any periodicity Whatever for the brief interval While its varying sonaiicc :icccrds with such pein this way Lhc apparatus may he sign-shad by any station. whatcver and then suhscqucntly put i to commin'iicaticn with that station cxclusivcly.

A further object of the invcntion is to dcvisc a method which shall be. economical and clllciont for securing the ahovc-namcd l'cainvention. consists suh. 'aulially in lhc and. scqucncc ol steg' and manipulaas will he niorc full wrcinalzcr so; i forth, and. iii y particularly poinlcd our. in

the appended. claims.

listening to thc accompanyi (ll'il,\\ll'l i have show). a diagrammatic vicxr oi tlic cir cuits and thc appliances which may hc uscd to carry out an. cinhodimcnt of tho present invention.

It is to he clearly understood that this in- .vcntion in its preferred aspect, wholly distinct from the phenomenon of cleqiziricrcsrc nance pro per, which relates to the surging of currents hac Ward and forward in a r 7 mmtor or circuit with enormously in a frequency. This ih-cncuienou forms l. hasis of al Wireless transmission and attcmpts have been made to adapt it to selective signaling by attuning the resonance ol the rc ceiving and transmitting circuits to corn:- spond with one another. But inasmuch as the electric resonance of circuits and conductors is of very uncertain and variahlc charactc'r, (inc to what is known as inultiplc TLSU'? nancc, such electric resonance cannot hc 'rc lied upon for selective signaling, any particular receiver hcing likely to respond to thc vrials of transmitting-stations oi widely dill crent periodicity from that which it is attuncd cation, however, does not rely upon the phesclectivc signaling propcrtics, but depends upon synchronizing mcchanicallppro luced vibrations of any sort Whose periodicity can be absolutely controlled and mainthined-at any fixed rate. Under these circumstances the resent method is not only arlap'lgcd to Wire css-telegraph transmission, when? each of the impulses received is itself composed oi alternatip" vibrations or waves, but is also applicable to inipulsc-currcnts through Wire circuits, or wireless transmission of messages by mere single electrostatic or electromagpracticed hciorc the advent of tho so-callcd Wireless tclcgraphy proper, as the term is 'r'iow uscd.

'Rcfcrring now to the drawing and thc vitrious views and 1clerence-signs thereon in which like parts are inlilicated by the same to receive. The method of the present applh netic'wavcs in accordance with the methoi'ls,

nonienon of electric resonance propcr for its KID . invention perfectly understood, I will deerated.

- phone-receiver S. As

scribe the general features of the coherer and other apparatus which I have employed. in practice for utilizing my method. Upon. a shaft or spindle 3 continuously rotated by the pulley i, and the band 5, I arrange a air of metallic contact-disks 6, 7, both of w ich are grounded on thee-halt so as to form a con tinuous electrical. conncction'between their peripheries. The eriphery of diskfi dips in a mercury-cup 8 W iich forms the terminal of the line-wire 1. An electrical contact 9 is s ring-pressed against the periphery of the 7 and constitutes the grtund terminal 16 of the wireless or othe. telegraph system.

11 denotes a spring-pressed arm carryinga pad 12 which bears upon the periphery of the disk 7 and acts to maintain the same in a clean and proper condition. This constitutca the coherer and its operation will he later described.

13 denotes a mechanical'vibrator of any suitable or desired'form. I have sh own this vibrator as comprising one arm of a tuningforls, but it is obvious that a reed or any form of rotary, or other mechanical. vibrator may be employed. The "vibrator has mounted upon it an. electrical contact which is adapted to make and break an electrical circuit when the vibrator is operated.

- I have shown a convenient form of contact "comprising a Wheel 14.- continuously rotated by a band 15 and disposed adjacent to a contact 16' of the local circuit 1, V, which also includes a battery B, and a sounder or telethe fork 13 vibrates, cciit'act-is successivel made at points 14., 15, and the sounder or telephone-receiver S is op For the purposes of my invention I provide means to'changethe periodicity of the mechanical vibrator 13 and in the drawing have illustrated a convenient construction, diagrammatically shown insection, comprising a mercury-reservoir 17, closed'by a dia -hragm 18 and having an outlet- 1pc 19 which leads u i to a cavity 20 Wit .liIl the fork 13. 21 indicates a presser-plate sup ported on connections 22 and driven from a continuously-rotating shaft 23 which is driven by a secono continuously-rotatin shaft 24, through any suitable caring 25 W ereby the mercury-column slow y rises and falls Within tonne, of a Wireless-telegra h receivirig-staenacts the fork 13, coeratively disengaged from the s aft 23 for t. c urpose of discontinuing the. rotation of The shaft 24 is ada tedto the atter, and for this purpose. Ivhave dia.

grammatically shown the shaft 24 upon an arm 26 moved by a ma not 27, so that when the magnet is energize the shaft 24 will be 0 eratively disconnected from the part 23, t ereb fixing; the mercury-column within the for (L 13. The magnet v27 is included in a local circuit m,-m which is adapted to be closed to energize the magnet by the vibrations of the fork 13 which closes the contact m. it is to be understood that the appara- .tus here diagrammatically shown is merely taken for the purposes of illustration to show' a practical way in which the method of my invention can be embodied.

28 designates a magnet dii' fei'entially we and With opposed windings o, ri which are joined at to one terminal of a battery B and whose other ends are connected respectively at to the termina n of the'battery B is also joined to the line-terminal 1, whereby there is formed a continuously-closed circuit through the winding n of the diiierential magnet 28. The circuit through the other Winding a T his by t ose skilled in theart, while the battery B is of low voltage, one volt or less, so that no current norma y passes winding I will now' describe the steps, and sequence can only i be completed through the coherer 2. 'c'oherer, of WhiltBVGT form, interposes a norrnall high resistance, as

n to the line connection 1 and at ound connection 10. The second 1 will be understood.

of operations, which constitute my invention,

and in the performance of which the above apparatus operates. I do not Wish. to con fine myself to the specific a paratus shown or to any of the details or iisatures thereof, since these are not essential to carry out my invention, but merely a convenient and practical construction. Any .form of co erer. could be substituted for the one here shown; various forms of mechanical vibrator can employed, and the magnet-28 may have a single core if desired which carrieslboth-wincl in s n and n 1 lhe electrical impulses induced in theatr tion pass downward throng the connection 1 into the mercury cup 8 and intotheidishs 6 and 7. The dish 7 carries on'its surface by reason of its rotation, a very and across this, air gapthefperiodic cu rircnt; leaps to the contact Q-and'td the rlgloun complete the circuit in the usua. fllhe action of th current inleaping scribes the gap establishes a local-hatterywircuit as follows:

B n n n contented), 7, cup 8, baclrto the battery Thol ect of energizing the coil n 'is to neutralize'the effect of t e Winding n which is continua ly excited by the battery, so that as the two windings-now oppose each Oil\(.i",'$i\(3 nizignel 25% loses its attractive force open the mechanical vibrator 33. Under these rirrnmsimiees {lie viln'zilor l3 begins to sway backward and forward, Wiill a rertnin periodicity, dopmnleiili on the mereurr-rol-- ninn or otli *1 means wliirii regulates said p ri0dieil in Llie meantime l'lie eonnerlion 22 is slowly ositillzilillg'. so that the morn-2r; slowly r' fork l3. l have found that :i romplete "vole ol' n evenwnt oi ill-3 mercury inslioul s min-- me or a: minute and :1. lisli gives good results in pf'zieiiiye.

if the 'periodir currents in {lie roimeei'ion are coming in. the form. oi' impulses regularly and sin-r ivel 'eni'ieringlsieiippsratus at delined and p operl the magnet 121*; Will in? em Willi sneli impulses and i irieelisnir. ..l vibrator il .i'iziced intervals of time,

ismii iliein EQ-blli if this vibrator mod the impulses, it will '1 and tiiiiie no 2-2, nolfvsible circuit. 14-,

'2 ound reeeive iciil vibrator not be attuned l. imp ise 1 nothing will r 1 t i 1 9 he} 0 i nhp en \nmi nil/le I.) Lid dug in lo elizinge Llie :liedy of the lifleCllfiilHizll v1- o ijlisi it 1:9 is tune, wk

brsLor the signin. if)

timed is iiiipnlsi i K el onus i, '1 i-lie ridgnei. 27 Lo 1'. o so sute-iiieiieiilelm-J .lir-reslter the INEI'iiK ieilzy ieal vierstori3 is fixed, and st w" uiliillt'fli impulses. Tili$- me impulses re sent in groinis to correspond Wi li lie dots and dsslies oil' he liiorse code, and ilie message is received in the sounder or I eplienereeeiver S from fie transmitng-st ition. in. die meantime ilie apparatus not :ill'eeted by messages from .121 lions to which the mechanical Vibrzinionienl zitliniied.

. f el we use noi :11: than r v iiilll the eonw 'ssiiion eol'npleied, the

perioilieit -rei ,'ing means 134 .is again storied into operation and ill apparatus is in eondition to (stall the iii; enLion signal of any i rzuismitLing-smlion. in order fliereiore lo liblizlll eoimniniiestion between a sending station and :1 l'EUCiViIlg-Slkliiol], lb is only neoessary for the former in send out a snesdy sir mm of impulses iii its ox n ride until a response (MUN I: l'rom some rem. lUg-Sialtilfl).

Wind l vleim isl. The method of delerting vibratory ourrents oi :i eonsliml. pi-iz'iodieity which eonsisis in subjw-Ling ii vibratory body to the influenee oi said. currents and simultzineonsly grad uallv altering the periodirity of said un il it is in tune will: thin; of said enrrezits.

The meii'ied oi signaling which consists subjecting vibratory body to succesized to eorrirspondthe bodv I l I l I l i I I i I I I I I I I I I I l I l i. l l I I l I I l I I I i l l l sive impulses, and simultaneously gradually r-lumging the periodirity oi the Vibratory body until its periodieir} cor -esponds to that ol' the impulses.

3. Tl) methoi'l of bringing 2i vibratory body into synelironism will) impulses oi" e.

1 ronstiim periodicity, which (onsisis in suli jerking it to the inIlneni-e oi said impulses, and simultaneously continuously changing the periodieiay of said bod from minimum to :L inaxin'ium or vire verso, uniil its periodieiiv eorresponds to tho t of lie vibratory impnls and 'iinslly automatically stopping said elizmges when. such rorrespondenee is obtained.

4'. The il'lGlllUIl of sigmiling which consists in transmitting elect-rim impulses of ii .lixed p riodieit receiving such impulses in ii eoi i Q forms part of a local eireuia in eluding slniigne, and snbjeeiing U. vibratory liody to the influence of said nmgnet and i' 'reduiiily elm; 11;; the periodieiby oi said body.

I}. The method of sigi'mling Wliieli (fOliNiSlf-i illJ'CCQlfiIig in'ipulses in a (winner which forms part0? loeiil circuit including a but and a magnet, siil ieeling s vibrato y body so the inlluem-e of said magnet, 2 sally changing the periodicity of SZLlL and finally closing a, local. circuit by menus said. body.

body

oi reeeiving impulses in a (.lUil'SICI, ez-icli inrpulselaeing composed of periodic currents oi iiigli frequency, eslsblisliing a lo tiLl circuit through time eolierer by means of said periodie currents whereby the perioeie currents are transformed. into simple impulses in tlie lorsl eirenii, and. subjecting a. meelianirzil vibrator liawin i a eontinuouslywhunging periodicity to said local impulses.

'1. The method oi. signaling which eon. sis in initially transmitting high frequency waives, divided info separate impulses to a rolierer,'esiaililisliing a eiroul inrlnding EL loeal battery though the eolierer by means oi said periodie currenis Wl'\(?i'(3l.) Y the periodir currents are Mansiormed into single inipnlses in the lo nil circuit, subjeeting zi ineelisnieal vibrator lowing a grzidwilly-(changin periodirity to said impulses and liniilly l 11;; the periodieil' of said vibrator.

b. The method 0 deleeting vibratory eurrenis which consists in subjecting a vibratory body to the influence of said currents and continuously changing the periodicity of the body until it is attuned to said vibratory eurrents and then finally lining the periodiei y of said vibratory body.

9. The method el. signaling which consists in trsnslnitbing high-frequency WiLVOS di- Viilil into impulses, transforming sand waves into simple impulse-currents, transforming said currents into pulsstiiiq magnetic force of corresponding periodicity, subjecting ii JIO ' Waves separated into groups of acermm pemechanical vibrator having a graduallychanging periodicity in said; magnetic farce; and finally transforming the vlbmtions 01? said mechanical vibrator into sound.

10'. The method of signaling which consists in transforming electric enmnetiqns or Usists trsmefonm'ng electric emanapicns or "Waves into simpleuafmisc-cmwems, tramsforming said; impulsemmrent-s into pulsating magnetic force, subjecising a mechanical vi brawl having a. changing periodicity to said nmgnetic force and. fitmll cutcmetically fixing the perisdicity cf ain vibrator when it is attuned '60 the magnetic impulses. M In witness whereof I subscflbe my wire in the presence 0?? two WitHBSSG-S.

SEEPHEIk DUE LEY FIELD.

-Witneeeesi I 1.1mm FENN, heme H. FENN ricdicity into simple impmlsemmiems, bramfm-ming' said impulse-currents inac pulsating magnetic force, subjecting a mecbcnieei Vi-- meter having a changing peziedieimy (we said pulsating magnetic fOIFCE, and E. 37 "fixing the peri dicity of the mechanical. 'v'i'm'ctor whexi it is attuned to said magnefiaic force 11. The method of signaling which ccn- 

